This application claims the benefit of the Jul. 8, 2008 filing date of provisional patent application Ser. No. 61/079,048.
Data processors, even more than most computer components, typically generate excessive heat during operation. If allowed to accumulate, the heat can impair, damage, and/or destroy the data processors; in addition, the heat can pose problems for user safety and comfort. Accordingly, a heat sink is typically used to conduct heat away from the processor and radiate it into the surrounding air. A fan is typically used to dissipate the air from the vicinity of the processor so that the heat sink can continue to cool the processor efficiently.
However, not only do the fans consume power and dissipate heat themselves, but they also generate noise that can negatively impact the user experience. For this reason, fans are often controlled as a function of the processor's temperature so that they are operational when needed and their speed of operation is not much more than needed for cooling purposes.
So that the fan is not constantly accelerating and decelerating, some hysteresis is built into the control method for the fan. In other words, for any given fan speed, the threshold temperature for ramping up the fan speed is higher than the threshold for ramping down the fan speed. However, despite these measures, fan activity can negatively impact the user experience and a solution is needed that reduces this negative impact.